Commercial passenger airplanes are typically designed to provide the maximum comfort and convenience for passengers by providing such features as overhead fans, lights, stewardess call buttons, stereo headphones and movies. The size and weight of such features is necessarily limited in order that the airplane may carry the maximum number of passengers with as much passenger space as possible. Accordingly, because each passenger must exercise control over his own overhead fan, light and stewardess call button, most of the control hardware and cabling is provided in the overhead ceiling above the passengers, since this represents the simplest arrangement for all of the control lines and control hardware.
It would be desirable to provide for passenger control of all the foregoing items in the armrest of each passenger chair on an individual basis. It might be possible to simply install a number of switches in the arm of the passenger chair and connect them through wires or cabling to the hardware and wiring already existing in the overhead ceiling. However, this would not be suitable because the installation of electrical wiring between the passenger seat and the ceiling makes such a device impractical and expensive to retrofit on existing airliners.